package com.ucd.common.utils;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

/**
 * RSA加密解密
 *
 * @author ruoyi
 **/
public class RSAUtils {
	// Rsa 私钥
	public static String privateKey =
			"MIICdgIBADANBgkqhkiG9w0BAQEFAASCAmAwggJcAgEAAoGBAJqS/OfiCoMx8TMB" +
					"MIQp/NOyN8wlTd+0yL4BrCqToVa+RB/k/lM2m+n6urmELiENaxsNtVAdBknjH4VT" +
					"ZjM1FbH23RNTaRac8D94qAhph0IgGzeEWO7VZL1T2hT8wNvqo4TFX/QSza4EFmgF" +
					"T+W8JKlgO8zdsxmhTjMnvdMxY44nAgMBAAECgYB0/X8Q+hI+zdPiaKoRvb2vdBmr" +
					"Fyjjge7VcGqgJvBbuNHS2fxres9yveQJeTN4rLE93pg2NGGIFrDKth6J70mlJTYy" +
					"yUZwt914CpL4qROIIPsWCfHyv8eaEgeQwwzxhBEKW/RdOIWXS7YFYxALvgFHY4Oh" +
					"bUP16wfKMNTzJ//LAQJBAMcRwxs0B/h45fZBRnmHx8QIlvq+BQ94srmcaRyQWfYE" +
					"RqHfUWKRSwdLl++n9gco2eT/EoEJPM8aKdMdBPA7CkECQQDGx6Yk23Cw7JGRnxGl" +
					"HreJVunMhhb8UWqJ4dS87jSYljVpTBbxQEIoARywqrgcjQvklx1DqpmD9ngAaf67" +
					"mu5nAkEAtm7Uuu1oEJHbTV5s05tXu5OTqZ7SzGb0g52PxpmTmB47DMW3s/krJThl" +
					"uT/X/J+3cGFB9/cbP0De65ZAnFe/AQJAR07bpSErXeyfk9Oyar+IK7aIDJyVplI2" +
					"m9vtixEQwSQxaOKo4Eai9OLhPecgQO3ANHKZRuruQ06pYcykWvyLRQJAHc8EHIl1" +
					"Fx4qzRVtvqytfFMUEiuvfCDwS4Uk7KrslWPg4GLSXTDl3jZRfWzqHkL6r7bRp1VP" +
					"cI3Z7k0HAc5dMQ==";

	/**
	 * 私钥解密
	 *
	 * @param text 待解密的文本
	 * @return 解密后的文本
	 */
	public static String decryptByPrivateKey(String text) throws Exception {
		return decryptByPrivateKey(privateKey, text);
	}

	/**
	 * 公钥解密
	 *
	 * @param publicKeyString 公钥
	 * @param text            待解密的信息
	 * @return 解密后的文本
	 */
	public static String decryptByPublicKey(String publicKeyString, String text) throws Exception {
		X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
		KeyFactory keyFactory = KeyFactory.getInstance("RSA");
		PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
		Cipher cipher = Cipher.getInstance("RSA");
		cipher.init(Cipher.DECRYPT_MODE, publicKey);
		byte[] result = cipher.doFinal(Base64.decodeBase64(text));
		return new String(result);
	}

	/**
	 * 私钥加密
	 *
	 * @param privateKeyString 私钥
	 * @param text             待加密的信息
	 * @return 加密后的文本
	 */
	public static String encryptByPrivateKey(String privateKeyString, String text) throws Exception {
		PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
		KeyFactory keyFactory = KeyFactory.getInstance("RSA");
		PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
		Cipher cipher = Cipher.getInstance("RSA");
		cipher.init(Cipher.ENCRYPT_MODE, privateKey);
		byte[] result = cipher.doFinal(text.getBytes());
		return Base64.encodeBase64String(result);
	}

	/**
	 * 私钥解密
	 *
	 * @param privateKeyString 私钥
	 * @param text             待解密的文本
	 * @return 解密后的文本
	 */
	public static String decryptByPrivateKey(String privateKeyString, String text) throws Exception {
		PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
		KeyFactory keyFactory = KeyFactory.getInstance("RSA");
		PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
		Cipher cipher = Cipher.getInstance("RSA");
		cipher.init(Cipher.DECRYPT_MODE, privateKey);
		byte[] result = cipher.doFinal(Base64.decodeBase64(text));
		return new String(result);
	}

	/**
	 * 公钥加密
	 *
	 * @param publicKeyString 公钥
	 * @param text            待加密的文本
	 * @return 加密后的文本
	 */
	public static String encryptByPublicKey(String publicKeyString, String text) throws Exception {
		X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
		KeyFactory keyFactory = KeyFactory.getInstance("RSA");
		PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
		Cipher cipher = Cipher.getInstance("RSA");
		cipher.init(Cipher.ENCRYPT_MODE, publicKey);
		byte[] result = cipher.doFinal(text.getBytes());
		return Base64.encodeBase64String(result);
	}

	/**
	 * 构建RSA密钥对
	 *
	 * @return 生成后的公私钥信息
	 */
	public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException {
		KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
		keyPairGenerator.initialize(1024);
		KeyPair keyPair = keyPairGenerator.generateKeyPair();
		RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
		RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
		String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
		String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
		return new RsaKeyPair(publicKeyString, privateKeyString);
	}

	/**
	 * RSA密钥对对象
	 */
	public static class RsaKeyPair {
		private final String publicKey;
		private final String privateKey;

		public RsaKeyPair(String publicKey, String privateKey) {
			this.publicKey = publicKey;
			this.privateKey = privateKey;
		}

		public String getPublicKey() {
			return publicKey;
		}

		public String getPrivateKey() {
			return privateKey;
		}
	}
}